Building a Eendracht class battlecruiser
From a post made by 1Big Rich in The Naval Fiction Board, concerning the Eendracht class battlecruisers who appear in the A stronger Netherlands navy timeline I have created. This is the post he made about the Eendracht class battlecruisers. I've been contemplating an RNN G3 as described by Terminus. A couple of initial thoughts; the RNN would be designing this ship when Dunquerque was laid down. Details of the later may or may not be known to the Dutch, but if they are, the French ship would be a much newer design than the 12 year-old concept of G3. Also, the RN had moved beyond G3 and N3 layouts. First F2 and F3, then with O3, the design that became Nelson and Rodney. F2 or F3 seem much better starting points for the Dutch if they're cooperating with the RN, with an all-forward layout rather than the break for the con. Both featured three main battery turrets, F2 featuring six 15in guns, and F3 with 9 15in guns. (recall the RN post-war design featured a letter for the design, and a number reflecting the number of guns in the main battery turrets, i.e, K3 was design K with 3-gun turrets, K2 was design K with twin turrets. The Roman Numeral battleships are another post.) F2 was the faster, to be 30 knots light and 29 knots deep, while F3 was to be 29 knots light and 28.5 deep. All that said, I tried to sketch what I thought a Netherlands-ized light G3 might look like. I have two concepts, the first reflecting Terminus' idea, with 6in secondaries. Armor follows the G3 philosophy with better protection for the magazines. Sims follow, though I will reiterate my reservations regarding the sim's ability to deal with the fast ships of the '30s and '40s accurately. I tried to sim them at 35,000 tons, as the treaties would be in effect, and going much larger might cause the collapse of the treaty system, which I see as a detriment to the Netherlands. If the sim is to be believed, there a little overweight, but that puts them in common with the treaty battleships of the 30s. http://i135.photobucket.com/albums/q160/lordroel_2007/Neth_g3_LR1936-DPII.jpg Eendracht, LR_Netherlands BC laid down 1934 Displacement: 33,811 t light; 35,455 t standard; 38,127 t normal; 40,264 t full load Dimensions: Length overall / water x beam x draught 772.78 ft / 771.00 ft x 101.71 ft x 31.17 ft (normal load) 235.54 m / 235.00 m x 31.00 m x 9.50 m Armament: 6 - 14.00" / 356 mm guns (2x3 guns), 1,590.00lbs / 721.21kg shells, 1934 Model Breech loading guns in turrets (on barbettes) on centreline, all forward, 1 raised mount - superfiring 3 - 14.00" / 356 mm guns (1x3 guns), 1,590.00lbs / 721.21kg shells, 1934 Model Breech loading guns in a turret (on a barbette) on centreline amidships 4 - 5.91" / 150 mm guns (2x2 guns), 102.98lbs / 46.71kg shells, 1934 Model Quick firing guns in deck mounts with hoists on side, evenly spread 4 - 5.91" / 150 mm guns (2x2 guns), 102.98lbs / 46.71kg shells, 1934 Model Quick firing guns in deck mounts with hoists on centreline, all aft, 1 raised mount - superfiring 4 - 4.72" / 120 mm guns in single mounts, 52.72lbs / 23.92kg shells, 1934 Model Anti-aircraft guns in deck mounts on side, evenly spread, all raised mounts Weight of broadside 15,345 lbs / 6,960 kg Shells per gun, main battery: 100 Armour: - Belts: Width (max) Length (avg) Height (avg) Main: 11.0" / 280 mm 426.51 ft / 130.00 m 18.04 ft / 5.50 m Ends: Unarmoured Main Belt covers 85 % of normal length - Torpedo Bulkhead: 2.24" / 57 mm 426.51 ft / 130.00 m 21.00 ft / 6.40 m - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max) Main: 14.0" / 356 mm 5.91" / 150 mm 12.2" / 310 mm 2nd: 14.0" / 356 mm 5.91" / 150 mm 12.2" / 310 mm 3rd: 0.98" / 25 mm 0.98" / 25 mm 0.98" / 25 mm 4th: 0.98" / 25 mm 0.98" / 25 mm 0.98" / 25 mm - Armour deck: 5.00" / 127 mm, Conning tower: 14.02" / 356 mm Machinery: Oil fired boilers, steam turbines, Geared drive, 4 shafts, 139,735 shp / 104,242 Kw = 31.00 kts Range 10,000nm at 15.00 kts Bunker at max displacement = 4,809 tons Complement: 1,363 - 1,773 Cost: £15.470 million / $61.881 million Distribution of weights at normal displacement: Armament: 1,673 tons, 4.4 % Armour: 12,387 tons, 32.5 % - Belts: 3,755 tons, 9.8 % - Torpedo bulkhead: 744 tons, 2.0 % - Armament: 2,296 tons, 6.0 % - Armour Deck: 5,250 tons, 13.8 % - Conning Tower: 342 tons, 0.9 % Machinery: 4,020 tons, 10.5 % Hull, fittings & equipment: 15,651 tons, 41.1 % Fuel, ammunition & stores: 4,316 tons, 11.3 % Miscellaneous weights: 80 tons, 0.2 % Overall survivability and seakeeping ability: Survivability (Non-critical penetrating hits needed to sink ship): 54,623 lbs / 24,776 Kg = 39.8 x 14.0 " / 356 mm shells or 8.2 torpedoes Stability (Unstable if below 1.00): 1.10 Metacentric height 6.2 ft / 1.9 m Roll period: 17.2 seconds Steadiness - As gun platform (Average = 50 %): 59 % - Recoil effect (Restricted arc if above 1.00): 0.59 Seaboat quality (Average = 1.00): 1.00 Hull form characteristics: Hull has a flush deck and transom stern Block coefficient: 0.546 Length to Beam Ratio: 7.58 : 1 'Natural speed' for length: 32.24 kts Power going to wave formation at top speed: 53 % Trim (Max stability = 0, Max steadiness = 100): 59 Bow angle (Positive = bow angles forward): 5.00 degrees Stern overhang: 0.00 ft / 0.00 m Freeboard (% = measuring location as a percentage of overall length): - Stem: 20.34 ft / 6.20 m - Forecastle (17 %): 20.34 ft / 6.20 m - Mid (50 %): 20.34 ft / 6.20 m - Quarterdeck (15 %): 20.34 ft / 6.20 m - Stern: 20.34 ft / 6.20 m - Average freeboard: 20.34 ft / 6.20 m Ship tends to be wet forward Ship space, strength and comments: Space - Hull below water (magazines/engines, low = better): 85.1 % - Above water (accommodation/working, high = better): 161.3 % Waterplane Area: 56,756 Square feet or 5,273 Square metres Displacement factor (Displacement / loading): 113 % Structure weight / hull surface area: 204 lbs/sq ft or 996 Kg/sq metre Hull strength (Relative): - Cross-sectional: 0.97 - Longitudinal: 1.35 - Overall: 1.00 Hull space for machinery, storage, compartmentation is adequate Room for accommodation and workspaces is excellent Main Belt 10in over machinery, 12in over magazines Main deck 4.5in over machinery, 5.5in over magazines 80 tons flag facilities, catapult, aircraft +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ The above done, I started looking at the Bofors 120mm, a gun the Dutch used and planned for the 1047 battlecruisers. Laying the BC down around the mid-30s doesn't seem too early for a DP mount to be aboard a capital ship, and the Dutch seem to have had a good grasp of the air threat. So I re-sketched (and re-simmed) the light G3 for a DP secondary based on the 4.7in. http://i135.photobucket.com/albums/q160/lordroel_2007/Neth_g3_LR1936I.jpg Eendracht, LR_Netherlands BC laid down 1934 Displacement: 33,808 t light; 35,455 t standard; 38,127 t normal; 40,264 t full load Dimensions: Length overall / water x beam x draught 772.78 ft / 771.00 ft x 101.71 ft x 31.17 ft (normal load) 235.54 m / 235.00 m x 31.00 m x 9.50 m Armament: 6 - 14.00" / 356 mm guns (2x3 guns), 1,590.00lbs / 721.21kg shells, 1934 Model Breech loading guns in turrets (on barbettes) on centreline, all forward, 1 raised mount - superfiring 3 - 14.00" / 356 mm guns (1x3 guns), 1,590.00lbs / 721.21kg shells, 1934 Model Breech loading guns in a turret (on a barbette) on centreline amidships 12 - 4.72" / 120 mm guns (6x2 guns), 52.72lbs / 23.91kg shells, 1934 Model Quick firing guns in deck mounts with hoists on side, evenly spread, 4 raised mounts 4 - 4.72" / 120 mm guns (2x2 guns), 52.72lbs / 23.91kg shells, 1934 Model Quick firing guns in deck mounts with hoists on centreline, all aft, 1 raised mount - superfiring 4 - 4.72" / 120 mm guns in single mounts, 52.72lbs / 23.91kg shells, 1934 Model Anti-aircraft guns in deck mounts on side, evenly spread, all raised mounts Weight of broadside 15,364 lbs / 6,969 kg Shells per gun, main battery: 100 Armour: - Belts: Width (max) Length (avg) Height (avg) Main: 11.0" / 280 mm 426.51 ft / 130.00 m 18.04 ft / 5.50 m Ends: Unarmoured Main Belt covers 85 % of normal length Main belt does not fully cover magazines and engineering spaces - Torpedo Bulkhead: 2.24" / 57 mm 426.51 ft / 130.00 m 21.00 ft / 6.40 m - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max) Main: 14.0" / 356 mm 5.91" / 150 mm 12.2" / 310 mm 2nd: 14.0" / 356 mm 5.91" / 150 mm 12.2" / 310 mm 3rd: 0.98" / 25 mm 0.98" / 25 mm 0.98" / 25 mm 4th: 0.98" / 25 mm 0.98" / 25 mm 0.98" / 25 mm - Armour deck: 5.00" / 127 mm, Conning tower: 14.02" / 356 mm Machinery: Oil fired boilers, steam turbines, Geared drive, 4 shafts, 139,735 shp / 104,242 Kw = 31.00 kts Range 10,000nm at 15.00 kts Bunker at max displacement = 4,809 tons Complement: 1,363 - 1,773 Cost: £15.480 million / $61.920 million Distribution of weights at normal displacement: Armament: 1,675 tons, 4.4 % Armour: 12,406 tons, 32.5 % - Belts: 3,755 tons, 9.8 % - Torpedo bulkhead: 744 tons, 2.0 % - Armament: 2,315 tons, 6.1 % - Armour Deck: 5,250 tons, 13.8 % - Conning Tower: 342 tons, 0.9 % Machinery: 4,020 tons, 10.5 % Hull, fittings & equipment: 15,627 tons, 41.0 % Fuel, ammunition & stores: 4,319 tons, 11.3 % Miscellaneous weights: 80 tons, 0.2 % Overall survivability and seakeeping ability: Survivability (Non-critical penetrating hits needed to sink ship): 54,515 lbs / 24,727 Kg = 39.7 x 14.0 " / 356 mm shells or 8.2 torpedoes Stability (Unstable if below 1.00): 1.10 Metacentric height 6.1 ft / 1.9 m Roll period: 17.2 seconds Steadiness - As gun platform (Average = 50 %): 59 % - Recoil effect (Restricted arc if above 1.00): 0.59 Seaboat quality (Average = 1.00): 1.00 Hull form characteristics: Hull has a flush deck and transom stern Block coefficient: 0.546 Length to Beam Ratio: 7.58 : 1 'Natural speed' for length: 32.24 kts Power going to wave formation at top speed: 53 % Trim (Max stability = 0, Max steadiness = 100): 59 Bow angle (Positive = bow angles forward): 5.00 degrees Stern overhang: 0.00 ft / 0.00 m Freeboard (% = measuring location as a percentage of overall length): - Stem: 20.34 ft / 6.20 m - Forecastle (17 %): 20.34 ft / 6.20 m - Mid (50 %): 20.34 ft / 6.20 m - Quarterdeck (15 %): 20.34 ft / 6.20 m - Stern: 20.34 ft / 6.20 m - Average freeboard: 20.34 ft / 6.20 m Ship tends to be wet forward Ship space, strength and comments: Space - Hull below water (magazines/engines, low = better): 85.1 % - Above water (accommodation/working, high = better): 161.3 % Waterplane Area: 56,756 Square feet or 5,273 Square metres Displacement factor (Displacement / loading): 112 % Structure weight / hull surface area: 204 lbs/sq ft or 995 Kg/sq metre Hull strength (Relative): - Cross-sectional: 0.97 - Longitudinal: 1.34 - Overall: 1.00 Hull space for machinery, storage, compartmentation is adequate Room for accommodation and workspaces is excellent Main Belt 10in over machinery, 12in over magazines Main deck 4.5in over machinery, 5.5in over magazines 80 tons flag facilities, catapult, aircraft ++++++++++++++++++++++++++++++++++++++++++++++ With respect to the above, while I tried to keep things realistic, I just don't think that a light G3 is a good design for the RNN to base a capital ship on. For the RN it was fine, as were N3 and Nelsol. As battleline combatants, the need for all-bearing fire wasn't as important, and a simple change of direction could bring a target 'wooded' by the after superstructure in the the midships turrets firing arc(s). But in some of the confined waters around the NEI, such maneuvering room might not be readily available. And as only 2 capital ships available, I think all-bearing gunnery would be of much greater importance. I would expect the RNN to pursue a 3-3-A-3 layout as they did for the 1047s, if not a 2-2-A-2-2 (as QE or Maryland) or 4-4-A-4 (as in the original WWII-KGV or North Carolina concepts) layout if 14in guns were to the weapon of choice. Myself, I think they might be better served with well armored battlecruisers carrying 6 x 16in guns on 35,000 tons. My thoughts,